Fluid actuated pressure device



Dec. 30, 1952 .J. DUNGLER 2,623,361

FLUID ACTUATED PRESSURE DEVICE Filed Feb. 27. 1948 3 SheetsSheet lINVENTOR:

Dec. 30, 1952 DUNGLER 2,623,361

FLUID ACTUATED PRESSURE DEVICE Filed Feb. 27, 1948 3 Sheets-Sheet 2 LekDec. 30, 1952 J. DUNGLER 2,523,361

FLUID ACTUATED PRESSURE DEVICE Filed Feb. 27, 1948 5 Sheets-Sheet ISPatented Dec. 30, 1952 UNITED STATES PATENT OFFICE Application February27, 1948, Serial No. 11,711 In France October 25, 1947 11 Claims.

Many pressure exerting devices actuated by pneumatic or hydraulic meanshave been heretofore known. Such devices have the advantage of enablinga very flexible transmission and adjustment of the pressure to beobtained, but at the same time they have the drawback of requiring thecontinuous operation either of a compressor, or of a pump, therebycomplicating such equipments and making them uneconomical forcomparatively low-power plant.

The device according to the invention, which has the flexibility oftransmission and of adjustment of the known devices without having theaforesaid drawback, comprises, in combination, at least, a fluid-tightreservoir with flexible or deformable wall which contains a gaseous orliquid fluid, a rigid casing surrounding the reservoir in such a manneras to be in contact with the same except over a predetermined area, andmovable means adapted to exert a pressure against said area of thereservoir which is not in contact with the casing.

One of the main features of the invention is to provide means affordingsliding movement Within a casing of a piston or pistons against aresilient reservoir to cause the latter to perform displacement ofmachine parts.

According to the invention, the casing may be stationary so as to absorbthe pressure exerted by the piston on the reservoir.

According to another feature of the invention, the piston may co-operatewith stationary means which enable an adjustable pressure to be exertedagainst the reservoir, the casing being movable so as to be capable oftransmitting the pressure of the piston to a movable member secured tothe casing.

According to still another feature of the invention, the piston mayco-operate with movable actuating means interposed between the pistonand a movable member against which a pressure is to be exerted, thecasing in this case remaining stationary.

According to another feature of the invention, the opposite face of thepiston to the one that exerts a pressure against the reservoir maycooperate with an abutment secured to the casing in such a manner thatthe operation of the actuating means in one direction produces apressure on the movable member to be actuated, whereas the operation ofsaid means in the other direction mechanically effects the retraction ofthe movable member.

According to a further feature of the invention, the reservoir isequipped with a pressure 2 gauge and with fluid filling and emptyingmeans.

According to another feature of the invention, the fluid in thereservoir may be subjected to a predetermined filling pressure.

According to a still further feature of the invention, the casing may bestationary and be provided with a plurality of movable pistons, some ofwhich being driving pistons while the remaining ones are driven ordisplaced pistons.

According to another feature of the invention, the pistons of a devicecomprising a plurality of pistons may be of different diameters orcrosssections.

According to another feature of the invention, the cross-section of thecasing, and consequently that of the reservoir in contact with same mayvary along the length of these elements.

According to another feature of the invention, a single piston mayco-operate with two reservoirs located on either side of said piston inthe same casing.

According to a further feature of the invention, the device may be usedas a shock-absorber, the casing being secured to the member which is toabsorb the shocks, whereas the piston is secured to the member whosemovements are to be damped.

According to a still further feature of the invention, the device mayco-operate with the presser roller of a padder or foulard, a calender, awatermangle, a roller press for paper or the like.

According to a still further feature of the invention, a single pistonmay act on a plurality of reservoirs located in separate casings andexerting a pressure on one of them, means being provided for placing theseparate reservoirs in communication with one another.

Other features and advantages of the invention will become apparent fromthe ensuing description; reference will be made to the accompanyingdrawings in which: i

Fig. 1 is a longitudinal sectional view of a device according to theinvention used as a shockabsorber.

Fig. 2 is a longitudinal section of a: pressure device having a drivingpiston and a driven piston.

Fig. 3 is a section of a pressure device comprising a driving piston andtwo opposed driven Fig. 5 shows a pressure device with a differentialcross-section and a movable casing.

6 shows an elevational view of the application of the device accordingto the invention for operating the pressure roller of a foulard.

Fig. 7 shows a front view of the device according to Fig. 6, and

Fig. 3 is a similar view to that of Fig. show ing a modification.

The device shown in Fig. 1 comprises a hermetically closed reservoir iadapted to contain a gaseous or liquid fluid. Said reservoir hasflexiole fluid-tight walls which are preferably resilient. It may bemade of an impermeable fabric, rubber, or any other suitable flexible ordeformable material, and it may also be made of foil material.

The resilient fluid-tight reservoir 1 is housed within a casing 2forming a rigid cylindrical. metal tube. It should be noted that thecasing 22 surrounds the reservoir I over the entire outer face thereofexcept at the upper part which is located opposite a piston is. which isadapted to slide in the casing 2..

The piston 23 is secured to a tubular member i which is adapted to slidelengthwise and on the outside of the casing 2 whereby the latter forms aguide for the, piston 3. A lug 5 enables the movable system 3 l to befixed to a movable member, (not shown) the movements of which are to bedamped. The casing 2 is fixed by means of lug s to the member, (notshown) intended to absorb the shocks transmitted to the piston 3.

The reservoir I may be equipped. with a pressure gauge I, the pipe ofwhich passes through the wall of the casing 2, thereby enabling thepressure in the reservoir I to be read.

The above device operates as follows: when the piston 3 effects adownward movement by the action of a shock received by the movablemember (not shown) to which it is secured, it compresses the fluidcontained in the reservoir I, since the resiliency of'the walls of thereservoir I enables the piston 3 to effect its down-stroke by pushingback the wall of the reservoir I facing it, but owing to the fact thatthe remainder of said wall is in contact with the rigid casing 2, thecompression produced by the piston 3 cannot be compensated by acorresponding expansion of another part of the reservoir so as toincrease the pressure in the reservoir I. In this manner, the pressureexerted on the. piston 3 is transmitted to the stationary casing 2' bymeans of the pneumatic or hydraulic cushion formed by a.

the reservoir I. When the pressure on the piston 3 stops, all theelements resume their original position owing to the reaction of. thefluid contained in the reservoir I and to the resiliency of the wallsthereof.

It should be noted that enclosing the shockabsorbing fluid in thefluid-tight resilient reservoir I gives the device a practicallyunlimited life without risk of losses of the shock-absorbing fluid.

Fig. 2 shows the device according to the invention, as applied to apressure exerting device. It also comprises a fluid-tight reservoir Iwith resilient walls, which is housed inside a cylindrical casingcomprising two portions of different cross-sections 2 and 2 In thecasing i is adapted to slide a piston 8 secured to a piston rod 9 bymeans of which pressure, obtained, for example, from an adjustableoperating device (not shown), can be transmitted to the piston S andconsequently to 4 the surface of the reservoir I which is locatedopposite the piston 8.

Another piston III, the diameter of which is larger than that of thepiston 8, is adapted to slide in the portion 2* of the casing so as notto be in contact with that surface of the reservoir I which is exposedwithin the casing 2 A piston rod II issecured to the piston IE! on theone hand, and to a movableimember (not shown) which it is desired to besubjected to a pressure, such as a presser roller of a calender, orother machine, on the other hand.

The reservoir I is connected to a pipe I on which ismounted a pressuregauge I and a cap I2 for filling and emptying reservoir I. The pressuregauge I enables the instantaneous pressure in the reservoir I to beread. The fluid contained in the reservoir I may be subjected beforehandto a pressure which can be read on the pressure gauge I.

The above device operates as follows: A pressure, which. is exerted bythe piston 8 on the adjacent face of the. reservoir I by means of anymechanical actuating device (not shown), is transmitted by the fluidcontained in said reservoir I to theopposite surface which is in contactwith the piston III to thereby push said piston It back. Owing to thefact that the diameter of the piston I0 is larger than that of thepiston 8, the pressure exerted on the piston It is increased.

Fig. 3 shows a modification in which the fluid reservoir comprises two;inter communicating sections I and I which. are. housed in a rigidcasing comprising the two sections 2 and 2 havin different diameters.

In the casing section 2 there is slidab-ly disposeda piston 8 which iscoupled to a screwthreaded rod I3. which in turn is secured tohand-wheel I I and which screws into a stationary element I5.

The'casin section 2 contains two oppositely located pistons I6 and. IIwhich are in contact with the contiguous exposed end faces of. the

' reservoir section I where same is not surrounded by the casing 2 Thediameter of the pistons I6 and I1 is larger than that of the piston 8. Apressure gauge I enables the pressure inside the reservoir I -4 to beread.

The device operates in a similar manner as that explained withreference, to Fig. 2. By screwing the screw-threaded rod I3 into theelement I5 by means. of the hand-wheel It, the piston 8 is movedforwards so as to exert a pressure on the face of the reservoir I saidpressure being transmitted by means of the fluid contained in thereservoir W-I to the end faces and also to the pistons I5 and II whichare thus urged in outward direction. according to the arrows so as toexert in turn a pressure on associated members which it is desired tosubject to a pressure. In view of; the difierence in diameters of the;pistons I6" and I! with respect to piston 8 an increase in pressure onpistons It, I 7 takes place. By means of the screw I3, the pressureexerted on the piston 8 and consequently transmitted to the pistons I5and I? can be adjusted, and said pressure can be read on the pressuregauge I.

It should be. noted that the above device enables a given pressure to bemaintained indefinitely without requiring the operation of a pump orother machine, and without risk of loss of fluid.

Fig. 4 shows a modification in which a piston l8 located in a rigidcylindrical casing 22' is adapted to co-operate with two independentreservoirs and 2| arranged on either side of the piston 18 inside thecasing 2 The reservoir 2| is of toroidal shape so as to allow the pistonrod 19 to pass therethrough. The two reservoirs 20 and 2| are equippedwith pressure gauges I and with filling and emptying devices 12.

Whereas in the foregoing devices the actuating piston only acted in onedirection, the piston I8 of the above device acts in both directions,owing to the fact that it co-operates in one direction with thereservoir 20, and in the other direction with the reservoir 2|.

The device may be used as a shock-absorber. In that case, the piston rodI9 is secured to the movable member whose movements are to be damped,whereas the casing 2 which is intended to absorb the shocks by means ofthe fluids contained in the reservoirs 20 and 2|, is stationary.

The device can also be used as a pressure device which is intended totransmit an adjustable pressure to a movable member to be actuated intwo opposite directions. In this case, the piston rod I9 may be securedto any actuating device, whereas the casing 2 is directly or indirectlysecured to the movable member to be actuated.

Fig. 5 shows a modification of a pressure device provided with areservoir comprising two sections l and I housed inside a casing 2' ---2whose shape corresponds to that of said sections.

A piston 8, actuated by a screw-threaded rod 53 which is secured to ahand-wheel i5 and which screws into a stationary member i5, is adaptedto slide in the casing section 2 so as to exert a pressure on thesection P or" the reservoir, whereas the section 2 of the easing iscompletely closed in such a manner that a pressure exerted on the piston8 and consequently on the reservoir l--i tends to drive back the casing2 2 In practice, the casing E -2 may be secured to the movable member tobe actuated.

Figs. 6 and 7 show the application of the device according to theinvention to a foulard. On a framework 22 are mounted the bearings 23 ofa stationary roller 24, whereas the movable presser roller 25 isjournalled in bearings 26 mounted at an intermediate point of rockinglevers 27 which are pivotally connected at one of their ends, at 28, tothe framework of the machine, and at the other end, at 25, to a U-shapedstirrup 35. The stirrup 35 is provided with a central screw-threadedbush 5! into which screws a screw-threaded rod 32 secured to a handwheel33. The lower end of the rod 32 is coupled, by means of a couplingdevice 34 enabling the rod 32 to rotate, to a piston 35 adapted to slidein a cylindrical casing 36 in which is housed a reservoir 31 withresilient walls which enclose a gaseous or liquid fluid. The casing 36is fixed to the ground or to the framework of the machine by means oflugs 35*.

The reservoir 31 is equipped with a pressure gauge 38 and with a fillingand emptying cap or like device 39.

The piston 35 is provided with rear extensions 45 adapted to co-operatewith abutments 4! located on the open rear end of the cylinder casing35.

The foulard is driven in the usual manner by a power unit 42 comprisinga motor and a speed reducer which, by means of belts 43, actuates agearing comprising gear wheels 44. The cloth or other material treatedis shown at 45.

The above device operates as follows: when the hand-wheel 33 is actuatedso as to move the piston 35 downwards, said piston exerts a pressure onthe reservoir 3'! so as to compress the fluid contained in same. Owingto the fact that the cylindrical casing 35 and consequently thereservoir 3! are stationary, the compression of the fluid causes thebush 3| to move backwards and rock the lever 21 in such a manner as topress the presser roller 25 against the stationary roller 24. Thepressure set up can be read on the pressure gauge 38. It is thuspossible to produce an adjustable and permanent pressure between therollers 24 and 25.

When the hand-wheel 33 is rotated in the other direction so as towithdraw the piston 35, the pressure exerted on the reservoir 3! andconsequently on the presser roller 25 is first released. If thehand-wheel 33 is further rotated, the extensions 45 of the piston 35 arepressed against the abutments 4|, which, owing to the fact that theabutments 4! are stationary, has the effect of moving the bush 3|downwards and of rocking the lever 21 downwards so as to move thepresser roller 25 away from the stationary roller 24. It is thuspossible not only to adjust the pressure between the rollers 24 and 25,but also to move said rollers away from one another, for example inorder to insert the cloth 45.

Fig. 8 shows a modification of a foulard equipped with the deviceaccording to the invention. The frame 45 supports the bearings 41 of thestationary roller 48, whereas the presser roller 49 is journalled inbearings 59 secured to a stirrup 5| similar to the stirrup 35 of Fig.'7, said stirrup being journalled at 52 on a bracket secured to theframe 45. At its lower part, the stirrup 5| is secured to a cylinder 53provided with a resilient fluid reservoir 54 and a sliding piston 55adapted to exert a pressure on said reservoir. The piston 55 is coupledto a screwthreaded rod 56 which, by means of a hand-wheel 51, can bescrewed in both directions into a member 53 secured to the frame 45. Theopen rear end of the cylinder casing 53 is provided with abutments 59adapted to cooperate with rear extensions 60 of the piston 55. Thedevice operates as follows: By causing the piston 55 to move forwardinto the cylinder casing 53 upon actuating the hand-wheel 57, thepressure exerted thereby on the fluid contained in the reservoir 54causes the stirrup 5| to rock in such a manner as to press the presserroller 49 in the direction of the arrow Bl against the stationary roller45. By rotating the hand-wheel 5! in the opposite direction, thepressure between the rollers 48 and 45 is first eliminated, then whenthe extensions encounter the abutments 59, they move the cylinder 53 soas to rock the stirrup 5! in the direction of the arrow 62, which hasthe effect of moving the rollers 48 and 49 apart.

Of course, the embodiments hereinbeiore described and illustrated in thedrawings are only given by way of mere non-limitative examples, and itis possible to modify in any suitable manner, the shape, the nature, thearrangement and the mounting of their elements without exceeding thescope of the invention. Thus, the pressure device may comprise aplurality of actuating pistons, one of which may, for example, be usedfor a rough or preliminary adjustment, whereas the other is intended forthe final and accurate adjustment. The reservoir need not completelyfill the casing in such a manner that the pressure inside the reservoiris partly determined by the resilient deformation of same.

The-reservoir need not necessarily be completely separated from thecasing, but a portion of the walls of the reservoir and, of the casingmay comprise common elements.

Although theinvention has been described and illustrated as applied to ashock-absorber and also to a pressure device for foulard its use is inno way limited to the aforesaid applications but may cover the mostvaried fields wherein it is advantageous to use pneumatic or hydraulicpressure devices. Thus, the device according to the invention can beused for calenders, presses or other machines.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters Patent, is:

1.. Fluid-actuated pressure device comprising in. combination, at leastone fluid-tight close" reservoir, a deformable endless wall definingreservoir and hermetically enclosing a fluid therein, a rigid casingsurrounding said reservoir in such a manner as to be in contact with thewall of said reservoir except over a predetermined area. thereof, andmovably' arranged means adapted to exert a pressure on the surface ofsaid wall of said reservoir positioned at said area which is devoid ofcontact with said casing, said movable means comprising at least onepiston adapted to slide in said casing and conformed to the shape of thelatter.

2. In a pressure device, as set forth in claim 1, wherein said casing isstationary so as to absorb pressure exerted by said movable means on thereservoir.

3. In a pressure device, as set forth in claim 1, including a movablemember secured to said casing, stationary means arranged to take uppressure exerted by said movable means against the reservoir, saidcasing being movable so as to be capable of transmitting pressure of thepiston to said movable member.

4. In a pressure device, as set forth in claim 1, wherein a pistoncooperates with movable actuating means interposed between said pistonand a 8 movable member on, which a pressure is to be exerted, saidcasing being stationary.

5., Ina pressure. devicaas set forth in claim 1, wherein said movablemeans forms a piston, an abutment secured to said casing in such amanner that, by operating said piston in one direction a. pressure isexerted on a movable member to be actuated, whereas by operating saidpiston in opposite direction withdrawal or" the movable member ismechanically effected and the path of said piston is limited by saidabutment.

6. In a pressure device, as claimed in claim 1, wherein the reservoir isequipped with a pressure gauge and with filling and emptying means.

'7. In a pressure device, as claimed in claim 1, wherein fluid locatedin the reservoir subjected to predetermined, inner pressure.

8. In a pressure device, as claimed in aaim 1, wherein said casing isstationary and comprises a plurality of movable pistons, driving pistonsand driven pistons, respectively.

9. In a pressure device, as claimed in claim 1, wherein said movablemeans form pistons of different cross-sections.

10. In a pressure device, as claimed in claim 1, wherein thecross-section of the casing and that of the reservoir in contact withsaid casing vary along the length of said casing.

11. In a pressure device, as claimed in claim 1, including a singlepiston forming said movable means and cooperable with said reservoirextending on either side of said piston in the same casing.

JULIEN DUNGLER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 850,181 Podstata Apr. 16, 190?906,923 Podstata Dec. 15, 1903 1,995,659 Trier Mar. 26, 1935 2,178,490Nielsen Oct. 31, 1939 2,250,734- Thompson July 29, 1941

